Many big data and cloud computing systems are implemented using distributed cloud systems having multiple program threads running in parallel across multiple servers. These systems include data management systems, multiplayer gaming systems, workforce collaboration systems (e.g. Sharepoint®, Slack® and HipChat® collaboration software) among others. These systems include software infrastructures such as scale-out storage, computing frameworks, synchronization services and cluster management services. The reliability of these distributed cloud systems is extremely important. Unfortunately these systems are subject to distributed concurrency errors (bugs), referred to herein as DCbugs. DCbugs may be difficult to detect due to the large state space of the distributed cloud systems and may manifest non-deterministically depending on the timing of distributed computation and communication.